Obesity has become a pandemic disease as well as the increased incidences of diabetes mellitus, hypertension, congestive heart failure and other less life-threatening complications over the last 2-3 decades. The cost of obesity and morbid obesity and the attempts to reduce weight in obese individuals in the United States alone are in excess of $150 billion. The increased incidence of obesity runs parallel to the increase in incidence of diabetes, cardiovascular diseases and hypertension.
However, neither the innumerable weight loss diets, medications, nor even the radical approaches of surgery have produced long-term, effective results. Whatever good results have been achieved has been costly financially and health-wise. Many specialists attribute these trends to the culture of self-gratification, increasing psychological stress, food industries'successful advertisements of “processed foods,” fast-food venues for high caloric and high carbohydrate foods such as French fries, cookies, cakes, chocolates, and many other popular foods. In spite of the recognition of the problem in the last two decades, governmental educational attempts, news media and school campaigns have achieved little in solving the obesity problem.
In 1934, Walter Kempner made the observation that people using rice as a staple food “rarely had diseases such as hypertension and diabetes.” He established the world-famous Rice Diet Center and the “Rice Diet Program” in Durham, N.C., and specialized in the prevention, treatment and reversal of “obesity, heart disease, hypertension, diabetes, congestive heart failure and kidney disease.” However, successful results of loss of 100 pounds in six-month stays at “Rice House” were, unfortunately, reversed after patients returned to their homes and to their old eating habits. Attempts to bring about changes in eating behavior at so-called fat farms by use of psychotherapy, use of personal dietitians, etc., also have not been successful in achieving significant improvement in long-term results.
A recent popular diet is the low carbohydrate diet of Dr. Pierre Dukan of France. It has gained greater popularity among dieters than other commercial low-carbohydrate diets such as South Beach Diet, Zone Diet, Atkins diets, etc. However, since carbohydrates constitute the largest percentage of the public's diet (greater than 40%), any weight loss diet is very difficult to maintain for a long period as required to achieve good, long-term results in the processed-food culture most persons are exposed to.
Behavior modification, business-cultural changes, medical treatments and the offering myriads of restricted diets have not proved successful. It has been proposed to change so-called harmful processed foods into beneficial ones.
In 1980-1981, at the University of Toronto, Dr. David J. Jenkins developed the concept of the glycemic index (“GI”) while working with diabetic patients. Dr. Jenkins discovered that the best foods for diabetic patients were those with the lowest GI. The glycemic index is a measure of the effects of carbohydrates on blood sugar levels. Carbohydrates that break down quickly during digestion and release glucose rapidly into the bloodstream have a high GI. This concept is attributed to Dr. David J. Jenkins and his colleagues (D J Jenkins et al (1981) Am. J. Clin. Nutr. 34; 362-266) in their research to find out which foods were best for people with diabetes. A lower glycemic index suggests slower rates of digestion and absorption of the foods' carbohydrates and may also indicate greater extraction from the liver and periphery of the products of carbohydrate digestion. A lower glycemic response usually equates to a lower insulin demand but not always, and may improve long-term blood glucose control and blood lipids.
The glycemic index of a food is defined as the area under the two hour blood glucose response curve (AUC) following the ingestion of a fixed portion of carbohydrate (usually 50 g). The AUC of the test food is divided by the AUC of the standard (either glucose or white bread, giving two different definitions) and multiplied by 100. The average GI value is calculated from data collected in 10 human subjects. Both the standard and test food must contain an equal amount of available carbohydrate. The result gives a relative ranking for each tested food.
The current validated methods use glucose as the reference food, giving it a glycemic index value of 100 by definition. This has the advantages of being universal and producing maximum GI values of approximately 100. White bread can also be used as a reference food, giving a different set of GI values (if white bread=100, then glucose≈140). For people whose staple carbohydrate source is white bread, this has the advantage of conveying directly whether replacement of the dietary staple with a different food would result in faster or slower blood glucose response. The disadvantages with this system are that the reference food is not well-defined and the GI scale is culture-dependent.
GI values are commonly interpreted as follows:
Low GI55 or lessmost fruits and vegetables, legumes/pulses, whole grains, nuts, fructose and products low in carbohydratesMedium GI56-69whole wheat products, basmati rice, sweet potato, sucrose,baked potatoesHigh GI70 and abovewhite bread, most white rices, corn flakes, extruded breakfastcereals, glucose, maltose
A low-GI food will release glucose more slowly and steadily, which leads to more suitable after-meal blood glucose readings. A high-GI food causes a more rapid rise in blood glucose levels and is suitable for energy recovery after exercise or for a person experiencing hypoglycemia.
The glycemic index can be applied only to foods with a reasonable carbohydrate content, as the test relies on subjects consuming enough of the test food to yield about 50 g of available carbohydrate. Many fruits and vegetables (but not potatoes) contain very little carbohydrate per serving, and the average person is not likely to eat 50 g of carbohydrate from these foods. Fruits and vegetables tend to have a low glycemic index and a low glycemic load. Alcoholic beverages have been reported to have low GI values, but it should be noted that beer has a moderate GI.
Many modern diets rely on the glycemic index, including the South Beach Diet, Transitions by Market America and NutriSystem Nourish Diet. However, others have pointed out that foods generally considered to be unhealthy can have a low glycemic index, for instance, chocolate cake (GI 38), ice cream (37), or pure fructose (19), whereas foods like potatoes and rice, eaten in countries with low rates of diabetes, have GIs around 100.
Several lines of recent scientific evidence have shown that individuals who followed a low-GI diet over many years were at a significantly lower risk for developing both type 2 diabetes and coronary heart disease than others. High blood glucose levels or repeated glycemic “spikes” following a meal may promote these diseases by increasing oxidative stress to the vasculature and also by the direct increase in insulin levels.
In the past, postprandial hyperglycemia has been considered a risk factor associated mainly with diabetes. However, more recent evidence shows that it also presents an increased risk for atherosclerosis in the non-diabetic population and that high GI diets and high blood-sugar levels more generally and are related to kidney disease as well.
Recent animal research provides compelling evidence that high-GI carbohydrate is associated with increased risk of obesity. In human trials, it is often difficult to separate the effects from GI and other potentially confounding factors such as fiber content, palatability, and compliance.
If a person consumes 50% of his or her calories from carbohydrates, the glycemic index can enable him or her to consume the same number of calories and have lower, more stable glucose and insulin levels.
It would be very important to be able to lower the glycemic indices of foods for health purposes to provide healthier foods than those presently available.
The process technique of the invention reduces significantly the natural glycemic indices of foods by treatment of the food to reduce its glycemic index. It therefore occurred to the inventor that his could be accomplished by treatment of the food to remove the water-soluble starch.